JP5797123B2 - Vehicle and vehicle control device - Google Patents

Description

  The present invention relates to a control technique for a vehicle including a plurality of electric motors, including an electric motor that mainly outputs mechanical power toward drive wheels.

  For example, a vehicle described in Patent Document 1 has been proposed as a vehicle including a plurality of electric motors including an electric motor that mainly outputs mechanical power from a rotor toward a drive wheel. Also known is a technology for boosting electric power from a power storage device such as a secondary battery or a capacitor by a booster circuit such as a DC / DC converter and supplying it to a power converter such as an inverter or a DC chopper provided for each electric motor. It has been.

Japanese Patent No. 414749

  In a vehicle including a plurality of electric motors as described above, for example, an inverter or a direct current chopper is used as a power converter that converts electric power from a booster circuit into electric power supplied to the corresponding electric motor for each electric motor. Etc. are provided. Some of these power converters are connected in parallel to a common booster circuit and receive power from the booster circuit. Such power converters differ in voltage required to be applied (hereinafter referred to as required voltage) depending on the operating state of the corresponding electric motor. At this time, the vehicle control device needs to set the boost ratio in the booster circuit based on the highest voltage among the required voltages respectively corresponding to the electric motors.

  In a vehicle having such a booster circuit and having, as a prime mover, an electric motor (hereinafter referred to as a drive motor) that mainly outputs mechanical power from a rotor toward a drive wheel, the vehicle is running at a reduced speed. In some cases, the rotor of the drive motor may rotate in response to mechanical power from the drive wheels, so-called “accompanying” may occur. When the driving motor is not powering and no torque is generated in the rotor, when the rotor is rotated by receiving mechanical power from the driving wheels, the rotational speed of the rotor is reduced to the driving motor. An induced voltage may occur in proportion.

  When such a vehicle decelerates from a state of cruising at a relatively high vehicle speed, the induced voltage generated in the drive motor may become high if the rotor of the drive motor rotates due to rotation. At this time, even if no torque is generated in the rotor in the drive motor, the required voltage (hereinafter referred to as the drive motor) required to be applied to the power converter provided corresponding to the drive motor. The required voltage) must be set to a value higher than the induced voltage generated in the drive motor. When the drive motor required voltage is higher than the required voltage required to be applied to the power converter provided for the electric motor other than the drive motor, the booster circuit is set to the drive motor required voltage. Therefore, it becomes necessary to set the boost ratio in the booster circuit to a high value.

  The present invention has been made in view of the above, and it is an object of the present invention to provide a vehicle control technology capable of suppressing an increase in a set boost ratio in a boost circuit that boosts power from a power storage device. .

  In order to achieve the above object, a vehicle according to the present invention includes a plurality of electric motors including a driving motor that is an electric motor that mainly outputs mechanical power from a rotor toward driving wheels, and each electric motor. The booster circuit boosts the power from the power storage device that stores the power supplied to the electric motor, and the electric motor is provided corresponding to each electric motor, and is connected in parallel to the common booster circuit and received from the booster circuit. A power conversion circuit that converts electric power to electric power to be supplied to the corresponding electric motor, a drive motor separating clutch that is a clutch capable of interrupting power transmission between the drive wheel and the rotor of the drive motor, and the drive wheel When the induced voltage generated by the rotation of the rotor of the drive motor in response to the mechanical power from the motor is greater than or equal to the set voltage, the drive wheel and the rotor of the drive motor Kicking and a control device for controlling the drive motor disconnecting clutch so that power transmission is cut off in the released state.

  In the above vehicle, when the drive motor separating clutch is in a released state, the control device requests a drive motor request that is a required voltage that is required to be applied to a power conversion circuit provided corresponding to the drive motor. It is possible to set the boost ratio in the booster circuit based on the required voltage required to be applied to another power conversion circuit without considering the voltage.

  In the above vehicle, the drive motor may be a first electric motor in which the rotor rotates in conjunction with the drive wheel when the drive motor disconnecting clutch is in a connected state. One of them may be a second electric motor that operates primarily as a generator. In addition, the power converter includes a booster circuit that boosts DC power from the power storage device and converts it into higher voltage DC power, and a power converter circuit. The DC power from the boost converter is supplied to the first electric motor. A first inverter that converts AC power to be supplied and a second inverter that includes a power conversion circuit and converts DC power from the boost converter to AC power supplied to the second electric motor can be provided. .

  In addition, the vehicle control device according to the present invention includes a plurality of electric motors including a driving motor that is an electric motor that mainly outputs mechanical power from the rotor toward the driving wheels, and is supplied to each electric motor. A booster circuit that boosts power from a power storage device that stores electric power, and an electric motor that is provided corresponding to each electric motor and connected in parallel to a common booster circuit, and that receives the electric power received from the booster circuit. Vehicle that can be used in a vehicle having a power conversion circuit that converts electric power to be supplied to a motor and that can control a drive motor separating clutch that is a clutch that can cut off power transmission between a drive wheel and a rotor of the drive motor When the induced voltage generated when the rotor of the drive motor rotates by receiving mechanical power from the drive wheel is equal to or higher than the set voltage, As the power transmission between the rotor wheel and the drive motor is cut off, and controls the drive motor disconnecting clutch in a released state.

  In the above vehicle control device, when the drive motor separating clutch is in the released state, the drive motor required voltage that is a required voltage that is required to be applied to the power conversion circuit provided corresponding to the drive motor. Without considering the above, it is possible to set the boost ratio in the booster circuit based on the required voltage required to be applied to the other power conversion circuit.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that the boost ratio set in the booster circuit which boosts the electric power from an electrical storage apparatus increases, and can improve the power conversion efficiency in the said booster circuit.

It is a mimetic diagram showing the composition of the vehicles concerning an embodiment. It is a flowchart which shows the clutch connection / release control of the drive motor disengagement clutch which the vehicle control apparatus which concerns on embodiment performs. It is a flowchart which shows the boost ratio setting control of the boost converter which the vehicle control apparatus which concerns on embodiment performs.

  Hereinafter, embodiments of the present invention (hereinafter simply referred to as “embodiments”) will be described in detail with reference to the drawings. In addition, this invention is not limited to the following embodiment, A various change is possible in the range which does not deviate from the summary.

  First, the vehicle according to the present embodiment will be described with reference to FIG. FIG. 1 is a schematic diagram illustrating a configuration of a vehicle according to the present embodiment. An example of the vehicle according to the present embodiment is a hybrid vehicle including an electric motor and an internal combustion engine as a prime mover, and each of the front wheels and the rear wheels is rotationally driven by receiving mechanical power from a propulsion shaft. A wheel drive vehicle will be described.

  As shown in FIG. 1, a vehicle 1 is used as a first electric motor 10 mainly used for driving the vehicle 1 and mainly as a generator, as an electric motor capable of converting electric energy into mechanical work and outputting it. The second electric motor 20 is provided. In addition, the vehicle 1 has an internal combustion engine 5 as a prime mover that converts fuel energy into mechanical work by combustion and outputs the mechanical work. These are mounted on the vehicle 1 in combination with a power transmission device to be described later.

  As the internal combustion engine 5, a piston reciprocating engine in which a piston reciprocates in a cylinder is used. The internal combustion engine is provided with a fuel injection device, an ignition device, a throttle valve device, and the like (not shown), and outputs generated mechanical power from an engine output shaft (crankshaft) 6. The engine output shaft 6 is connected via a damper 8 to an input shaft 32 of a power split mechanism described later. In the following description, mechanical power output from the engine output shaft 6 by the internal combustion engine 5 is referred to as “engine output”, and torque acting on the engine output shaft 6, that is, load, is referred to as “engine torque”. The rotational speed of the engine output shaft 6 is referred to as “engine rotational speed”.

  The first electric motor 10 and the second electric motor 20 each have a function of converting supplied electric power into mechanical power and outputting it, and a function as a generator for converting input mechanical power into electric power. It is a rotating electrical machine, a so-called “motor generator”. As the first electric motor 10 and the second electric motor 20, permanent magnet type AC synchronous motors are used. The first electric motor 10 and the second electric motor 20 are respectively provided with stators 13 and 24 that receive a supply of three-phase AC power to form a rotating magnetic field, and rotors 11 and 22 that rotate by being attracted to the rotating magnetic field. The rotors 11 and 22 are configured to be able to input and output mechanical power.

  The first electric motor 10 is a “drive motor” that mainly outputs mechanical power from the rotor 11 toward the drive wheels 77 and 99. In addition, the 1st electric motor 10 is comprised so that mechanical power received with the rotor 11 can be converted into electric power by operating as a generator. On the other hand, the second electric motor 20 is a “power generation motor” that operates mainly as a generator that converts mechanical power received by the rotor 22 into electric power. The second electric motor 20 is configured to be able to output mechanical power from the rotor 22.

  In the following description, the mechanical power output from the rotor 11 by the first electric motor 10 is referred to as “first motor output”, and the torque generated in the rotor 11, that is, the rotational load, is referred to as “first motor torque”. . The rotation speed of the rotor 11 of the first electric motor 10 is referred to as “first motor rotation speed”. Similarly, the mechanical power output from the rotor 22 by the second electric motor 20 is referred to as “second motor output”, and the torque generated in the rotor, that is, the rotational load is referred to as “second motor torque”. The rotation speed is referred to as “second motor rotation speed”.

  Further, the vehicle 1 receives mechanical power output from the internal combustion engine 5 by the input shaft 32 and can be divided into mechanical power directed to the second electric motor 20 and mechanical power directed to the drive wheels 77 and 99. A simple planetary planetary gear unit 30 is provided as a dividing mechanism.

  The planetary gear device 30 is coupled to the input shaft 32 and supports a planetary carrier 33 that rotatably supports the first planetary pinion 35, a first sun gear 36 that meshes with the first planetary pinion 35, and a first planetary pinion 35. And a ring gear 44 that meshes with each other. A drive gear 45 that outputs mechanical power toward the propulsion shaft 60 is coupled to the ring gear 44.

  The first sun gear 36 is provided coaxially with the input shaft 32 and is coupled to a gear 38 that drives the second electric motor 20 via a first hollow shaft 37 through which the input shaft 32 passes. The gear 38 meshes with a gear 39 coupled to the rotor 22 of the second electric motor 20 via the output shaft 40. Thus, the first sun gear 36 is engaged with the rotor 22 of the second electric motor 20. That is, the first sun gear 36 rotates in conjunction with the rotor 22 of the second electric motor 20.

  The planetary gear device 30 as the power split mechanism configured as described above can receive the engine output received by the input shaft 32 and transmitted to the planetary carrier 33 into the ring gear 44 and the first sun gear 36. ing. Of the engine output, mechanical power transmitted to the first sun gear 36 is transmitted to the rotor 22 and converted into electric power by operating the second electric motor 20 as a generator. On the other hand, the mechanical power transmitted from the planetary carrier 33 to the ring gear 44 is transmitted toward the drive wheels 77 and 99.

  The vehicle 1 also has a mechanism (hereinafter referred to as a speed increasing mechanism) 50 for increasing the rotational speed of the ring gear 44 with respect to the planetary carrier 33. The speed increasing mechanism 50 shares the power split mechanism described above with the planetary carrier 33 and the ring gear 44 of the planetary gear device 30. The speed increasing mechanism 50 is rotatably supported by the planetary carrier 33, shares the first planetary pinion 35 and the planetary carrier 33, and meshes with the second planetary pinion 51 that rotates integrally with the second planetary pinion 51. Two sun gears 52 are provided. The second sun gear 52 has a larger number of teeth than the first sun gear 36. The speed increasing mechanism 50 further brakes and stops the rotation of the second sun gear 52, and increases the rotational speed of the ring gear 44 relative to the rotational speed of the planetary carrier 33. B.

  The speed increasing brake B has a moving body coupled to the second sun gear 52 and a stationary body coupled to the vehicle 1, a moving body 54 that rotates integrally with the second sun gear 52, and a stationary body 55. And the rotation of the second sun gear 52 can be braked and stopped. When the speed increasing brake B is controlled to a “stop state” in which the rotation of the moving body 54 is stopped, the rotation of the second sun gear 52 is stopped, and the rotation speed of the ring gear 44 is set to a constant ratio with respect to the rotation speed of the planetary carrier 33. It is possible to increase the speed.

  In this specification, a state where a brake (for example, the speed increasing brake B) is operated to stop the moving body from rotating and is stopped is referred to as a “stop state”. On the other hand, a state where the brake is not operated and the moving body freely rotates with respect to the stationary body is referred to as a “non-operating state”. A state in which the moving body and the stationary body are in contact with each other and the rotation of the moving body is braked is referred to as a “braking state”. That is, the “braking state” includes the “stop state” described above.

  Further, in this specification, the clutch (for example, the coupling clutch A, the planetary gear side clutch C, the driving motor disconnecting clutch D, the transfer clutch 84) is not operated, and the driving side rotating member and the driven side rotating member are A state in which power transmission between the two is interrupted is referred to as a “released state”. On the other hand, a state where the clutch is operated and the driving side rotating member and the driven side rotating member rotate together at the same rotational speed is referred to as a “connected state”. In addition, a state where the driving-side rotating member and the driven-side rotating member are engaged and torque is transmitted between these rotating members is referred to as an “engaged state”. That is, the “engaged state” includes the “connected state” described above.

  The vehicle 1 also has a coupling clutch A that couples the planetary carrier 33 and the ring gear 44. In the present embodiment, the connection clutch A is configured as a meshing clutch. The coupling clutch A engages the rotating member 47 coupled to the input shaft 32 and the planetary carrier 33 with the rotating member 46 coupled to the drive gear 45 and the ring gear 44, thereby causing the planetary carrier 33 and the ring gear 44 to engage with each other. Can be linked. That is, by controlling the connection clutch A to the connected state, the ring gear 44, the planetary carrier 33, the first sun gear 36, the second sun gear 52, and the drive gear 45 rotate together at the same rotational speed.

  The drive gear 45 meshes with the driven gear 61, and the driven gear 61 can be engaged with the propulsion shaft 60 via a clutch C described later. A front-side differential drive pinion 64 is coupled to the front-side tip of the propulsion shaft 60, and the pinion 64 rotates and drives a ring gear 72 fixed to the front-side differential device 70. A front drive shaft 74 is coupled to the side gear of the front differential device 70, and a drive wheel (front wheel) 77 is coupled to the drive shaft 74.

  The propulsion shaft 60 is configured to be engageable with the drive gear 67 via a clutch D described later. The drive gear 67 is engaged with a driven gear 68, and the driven gear 68 is connected to the rotor 11 of the first electric motor 10 via a hollow shaft 69. That is, the rotor 11 of the first electric motor 10 rotates in conjunction with the drive gear 67.

  Further, a drive gear 81 is coupled to the propulsion shaft 60, and the drive gear 81 meshes with a driven gear 82. The driven gear 82 is coupled to an intermediate propulsion shaft 80 extending toward the rear side of the hollow shaft 69 described above. A transfer clutch 84 is connected to the rear side of the intermediate propulsion shaft 80, and a rear propulsion shaft 86 is connected to the rear side of the clutch 84. A rear-side differential drive pinion 88 is coupled to the rear-side tip of the rear-side propulsion shaft 86, and the pinion 88 rotationally drives a ring gear 92 fixed to the rear-side differential device 90. A rear drive shaft 94 is coupled to the side gear of the rear differential 90, and a drive wheel (rear wheel) 99 is coupled to the drive shaft 94.

  Further, the vehicle 1 has a planetary gear side as a clutch capable of interrupting power transmission between the propulsion shaft 60 rotating in conjunction with the drive wheel 77 and the drive gear 45 coupled to the ring gear 44 of the planetary gear device 30. A disconnecting clutch C is provided. In this embodiment, the planetary gear side separation clutch C is configured as a meshing clutch. The planetary gear side separation clutch C engages the driven gear 61 and the propelling shaft 60 by meshing the rotating member 62 coupled to the driven gear 61 that meshes with the drive gear 45 and the rotating member 63 coupled to the propelling shaft 60. Can be connected.

  That is, the planetary gear side separation clutch C is controlled to be connected to rotate the drive wheels 77 and 99, the propeller shaft 60, the drive gear 45, and the ring gear 44 of the planetary gear device 30 in conjunction with each other. On the other hand, the planetary gear side disconnecting clutch C is controlled to be in a released state, so that power transmission between the drive wheels 77 and 99 and the ring gear 44 of the planetary gear device 30 can be interrupted. That is, by disengaging the clutch C, power transmission between the engine output shaft 6 of the internal combustion engine 5 and the drive wheels 77 and 99, and the rotor 22 and the drive wheels 77 and 99 of the second electric motor 20 Power transmission between the two can be cut off.

  Further, the vehicle 1 is provided with a drive motor separating clutch D as a clutch for interrupting power transmission between the propulsion shaft 60 that rotates in conjunction with the drive wheels 77 and the rotor 11 of the first electric motor 10. Yes. In this embodiment, the drive motor separating clutch D is configured as a meshing clutch. The drive motor separating clutch D is formed by meshing a rotating member 66 coupled to a drive gear 67 that rotates in conjunction with the rotor 11 of the first electric motor 10 and a rotating member 65 coupled to the propulsion shaft 60. The propulsion shaft 60 and the drive gear 67 can be connected.

  In other words, the drive motor separating clutch D is controlled to be connected to rotate the drive wheel 77, the propulsion shaft 60, and the rotor 11 of the first electric motor 10 in conjunction with each other. On the other hand, the clutch D is configured to be able to cut off power transmission between the drive wheel 77 and the rotor 11 of the first electric motor 10 by being controlled to be in a released state.

  The vehicle 1 also has a power storage device 130 as a power source that stores electric power (electric energy) supplied to the first electric motor 10 and the second electric motor 20. The power storage device 130 is configured to be chargeable / dischargeable, and is configured to be able to store electric power collected from the first electric motor 10 and the second electric motor 20 that operate as a generator. For the power storage device 130, for example, a secondary battery, an electric double layer capacitor, or the like can be used. Note that the voltage of power applied by the power storage device 130 to a booster circuit of the boost converter 140 described later is referred to as “power supply voltage”.

  In addition, vehicle 1 is provided with a boost converter 140 having a booster circuit that boosts the DC power of the power supply voltage received from power storage device 130. Boost converter 140 is a so-called DC / DC converter that receives DC power of a power supply voltage (low voltage) from power storage device 130, boosts this by a booster circuit, and converts it into higher voltage DC power. The boosting ratio in the boosting circuit of boosting converter 140, that is, the ratio of the DC voltage (high voltage) applied to each inverter 110, 120 to the power supply voltage (low voltage) received from power storage device 140 is set by control device 100.

  Further, the vehicle 1 is provided with a first inverter 110 as a power converter that converts high-voltage DC power received from the boost converter 140 into three-phase AC power and supplies the AC power to the first electric motor 10. . Further, the vehicle 1 is provided with a second inverter 120 as a power converter that converts the high-voltage DC power received from the boost converter 140 into three-phase AC power and supplies it to the second electric motor 20. That is, the first inverter 110 is provided corresponding to the first electric motor 10, and the second inverter 120 is provided corresponding to the second electric motor 20.

  When the first electric motor 10 is operated as a generator, the first inverter 110 receives three-phase AC power from the stator 13 of the first electric motor 10, converts it to DC power, and converts it into a boost converter. 140 can be sent. Similarly, when the second electric motor 20 is operated as a generator, the second inverter 120 receives three-phase AC power from the stator 24 of the second electric motor 20, converts it to DC power, and boosts the voltage. It can be sent to the converter 140.

  The first inverter 110 has a “power conversion circuit” that is an electric circuit that converts the DC power boosted by the booster circuit of the boost converter 140 into AC power supplied to the first electric motor 10. Similarly, the second inverter 120 has a power conversion circuit that converts DC power boosted by the booster circuit of the boost converter 140 into AC power supplied to the second electric motor 20. The power conversion circuit of the first inverter 110 and the power conversion circuit of the second inverter 120 are connected in parallel to the boost circuit of the common boost converter 140.

  Note that the power conversion circuits of the first inverter 110 and the second inverter 120 convert the DC power supplied from the booster circuit of the boost converter 140 into AC power, and step down the power from the booster circuit, respectively. To the first electric motor 10 and the second electric motor 20. In other words, the power conversion circuits of the first inverter 110 and the second inverter 120 function as a “step-down circuit” that steps down the voltage boosted by the step-up circuit. In the following description, the ratio of the voltage boosted by the booster circuit to the voltage supplied to each electric motor is referred to as “step-down ratio”. As the above-described power conversion circuit (power converter, step-down circuit), in addition to the above-described inverter, a DC voltage is intermittently changed at a set frequency to change an average voltage applied to the electric motor. There is a “DC chopper”.

  Further, the vehicle 1 includes a first inverter 110 provided corresponding to the first electric motor 10, a second inverter 120 provided corresponding to the second electric motor 20, the internal combustion engine 5, the power storage device 130, a booster As a control means for controlling the converter 140, the coupling clutch A, the speed increasing brake B, the planetary gear side disconnecting clutch C, the driving motor disconnecting clutch D, and the like in cooperation, an electronic control unit for the vehicle 1 (hereinafter simply referred to as “control”). 100 ”(denoted“ device ”). The control device 100 includes a CPU as an arithmetic processing device, a RAM as a main storage device, a ROM as an auxiliary storage device (not shown), and the like. A program showing control processing for controlling various control objects described above, and constants set in advance in the control processing program (hereinafter referred to as control constants) are stored in advance in the ROM of the control device 100. Note that a variable set in the RAM in the above-described control process is referred to as a “control variable”.

  Further, the control device 100 receives a signal related to the rotational speed of the driving wheel from a wheel speed sensor (not shown) that can detect the rotational speed of the driving wheel 77 or the driving wheel 99, and the traveling speed of the vehicle 1 ( Hereinafter, the vehicle speed is estimated as a control variable. The control device 100 receives a signal related to the operation position of the accelerator pedal from an accelerator pedal position sensor (not shown) that detects the operation position of the accelerator pedal, and the operation amount of the accelerator pedal (hereinafter referred to as accelerator operation amount). Are estimated as control variables.

  The control device 100 receives a signal related to the rotational angle position of the rotor 11 from a resolver (not shown) that is a rotation sensor capable of detecting the rotational angle position of the rotor 11 of the first electric motor 10. Based on the signal, the first motor rotation speed is estimated as a control variable. Similarly, the control device 100 receives a signal related to the rotational angle position of the rotor 22 from a resolver (not shown) that is a rotation sensor capable of detecting the rotational angle position of the rotor 22 of the second electric motor 20. Based on the signal, the second motor rotation speed is estimated as a control variable. Note that the control device 100 can also estimate the first motor rotation speed as a control variable from the vehicle speed and the connection state of the drive motor disconnecting clutch D.

  Further, the control device 100 is required to be applied to the power conversion circuit of the first inverter 110 provided corresponding to the first electric motor 10 that is a drive motor, based on the control variables and control constants described above. The required voltage (hereinafter referred to as a drive motor required voltage) can be calculated as a control variable. Further, the control device 100 is a required voltage (hereinafter referred to as a generator request) that is required to be applied to the power conversion circuit of the second inverter 120 provided corresponding to the second electric motor 20 that operates mainly as a generator. (Denoted as voltage) can be calculated as a control variable.

  Control device 100 sets the boost ratio in the booster circuit of boost converter 140 based on the power supply voltage, the drive motor request voltage, and the generator request voltage. Control device 100 sets the step-up ratio based on the ratio between the drive motor request voltage and the generator request voltage that have a higher request voltage and the power supply voltage.

  In addition, the control device 100 controls power transmission / reception between the first inverter 110 and the first electric motor 10 to thereby perform power running / braking of the first electric motor 10, rotation direction of the rotor 11, and first motor rotation. The speed and the first motor torque (that is, the first motor output) can be controlled. Similarly, the control device 100 controls power transmission / reception between the second inverter 120 and the second electric motor 20 to thereby perform power running / braking of the second electric motor 20, rotation direction of the rotor 22, and second motor. The rotation speed and the second motor torque (that is, the second motor output) can be controlled.

  In addition, the control device 100 includes an operation state of the first electric motor 10 (first motor rotation speed and first motor torque), an operation state of the second electric motor 20 (second motor rotation speed and second motor torque), and The operation state (engine output and engine torque) of the internal combustion engine 5 can be controlled in a coordinated manner. In addition, the control device 100 determines the connection clutch A based on the control constants and control variables described above, the operating state of the internal combustion engine 5, the operating state of the first electric motor 10, and the operating state of the second electric motor 20. The connected / released state, the stopped state / non-operated state of the speed increasing brake B, the connected / released state of the planetary gear side disconnecting clutch C, and the connected / released state of the driving motor disconnecting clutch D can be controlled.

  In the vehicle 1 according to the present embodiment configured as described above, a first inverter 110 is provided corresponding to the first electric motor 10 that is a drive motor mainly used for driving the vehicle 1. A second inverter 120 is provided corresponding to the second electric motor 20 that is a power generation motor (generator) that mainly operates as a generator. The first inverter 110 and the second inverter 120 are connected in parallel to the common boost converter 140 and receive DC power from the boost converter 140. Each of the inverters 110 and 120 is a driving voltage that is a DC voltage required to be applied to the first inverter 110 corresponding to the driving motor according to the operating state of the first electric motor 10 and the second electric motor 20. The required motor voltage is different from the required generator voltage, which is a DC voltage required to be applied to the second inverter 120 corresponding to the power generation motor.

  At this time, control device 100 needs to set the boost ratio in the boost circuit of boost converter 140 based on the highest required voltage of the drive motor required voltage and the generator required voltage and the power supply voltage. That is, when the drive motor required voltage is higher than the generator required voltage, control device 100 does not consider the generator required voltage, and the DC power supplied from power storage device 130 to boost converter 140 without considering the generator required voltage. The boosting ratio in boost converter 140 is set based on the power supply voltage that is

  In the vehicle 1 having such a boosting converter 140 as a boosting circuit and the first electric motor 10 as a driving motor, the driving motor separating clutch D is engaged when the vehicle 1 is traveling at a reduced speed. In this case, even if the first electric motor 10 is not powered, a so-called “accompaniment” in which the rotor 11 rotates by receiving mechanical power from the drive wheels 77 may occur. When the first electric motor 10 does not generate torque in the rotor 11 and the rotor 11 is rotated, an induced voltage is generated in the first electric motor 10 approximately in proportion to the rotational speed of the rotor 11.

  In the case where the vehicle 1 is decelerated from a state where the vehicle 1 is cruising at a relatively high vehicle speed, the induced voltage generated in the first electric motor 10 may be increased when the rotor 11 is rotated together. At this time, even if no torque is generated in the rotor 11 in the electric motor 10, the drive motor required voltage corresponding to the first electric motor 10 needs to be set higher than the induced voltage. is there. When the drive motor request voltage is higher than the generator request voltage corresponding to second electric motor 20, boost converter 140 needs to set the boost ratio in boost converter 140 in accordance with the drive motor request voltage. As a result, there arises a problem that the step-up ratio increases as compared with the case where the drive motor required voltage is not considered.

  When the step-up ratio in step-up converter 140 increases, there arises a problem that the conversion efficiency of DC power in the inside thereof decreases. Further, due to the increase in the step-up ratio, in addition to the first inverter 110 provided corresponding to the driving motor, in the second inverter 120 connected in parallel to the step-up converter 140, the DC power is changed to the AC power. The step-down ratio at the time of conversion increases as compared with the case where the drive motor required voltage is not taken into consideration, which causes a problem that the conversion efficiency is lowered.

  Therefore, in the vehicle 1 according to the present embodiment, the control device 100 determines that the induced voltage generated in the first electric motor 10 that is a drive motor is greater than or equal to the set voltage between the drive wheel 77 and the rotor 11. The drive motor disconnecting clutch D is controlled to be in a disengaged state so that the power transmission is interrupted, and will be described below with reference to FIGS. 1, 2 and 3. FIG. 2 is a flowchart showing clutch engagement / disengagement control of the drive motor disengagement clutch executed by the control device according to the present embodiment. FIG. 3 is a flowchart showing the boost ratio setting control of the boost converter executed by the control device according to the present embodiment.

  First, clutch connection / release control of the drive motor separating clutch D executed by the vehicle control apparatus according to the present embodiment will be described with reference to FIGS. 1 and 2. While the vehicle 1 is traveling, the control device 100 repeatedly executes the clutch connection / release control. In the following description, for ease of explanation, a state in which the transfer clutch 84 is released and the power transmission between the propulsion shaft 60 and the rear driving wheel (rear wheel) 99 is interrupted will be described. To do.

  First, in step S02, the control device 100 acquires various control variables. The control variable includes “vehicle speed” that is the traveling speed of the vehicle 1. The vehicle speed can be obtained from the rotational speeds of the drive wheels 77 and 99. In addition, the control device 100 acquires the connection / release state of the drive motor disconnecting clutch D as a control variable.

  In step S04, the control device 100 calculates an induced voltage (drive motor induced voltage) generated in the first electric motor 10 that is a drive motor. This induced voltage is approximately proportional to the rotational speed (first motor rotational speed) of the rotor 11 of the first electric motor 10 that is a drive motor. When the drive motor separating clutch D is in the connected state, the vehicle speed and the first motor rotation speed are proportional to each other, and thus the control device 100 can calculate and estimate the induced voltage based on the vehicle speed. A table indicating the relationship of the induced voltage of the first electric motor 10 with respect to the vehicle speed is obtained in advance by a fitting experiment or the like, and is stored in advance in the ROM of the control device 100 as a control constant.

  In step S04, the control device 100 may calculate the induced voltage by directly detecting the induced voltage of the first electric motor 10 in the first electric motor 10. In this case, a table or the like indicating the relationship of the induced voltage with respect to the vehicle speed becomes unnecessary. In step S04, the control device 100 detects the “first motor rotation speed” that is the rotation speed of the rotor 11 of the first electric motor 10, and determines the first electric motor 10 based on the first motor rotation speed. The induced voltage generated may be calculated. The induced voltage of the first electric motor 10 can be calculated and estimated simply by obtaining a table indicating the relationship of the induced voltage with respect to the first motor rotation speed in advance.

  In step S06, control device 100 determines whether or not the calculated drive motor induced voltage is equal to or higher than a preset set voltage. The set voltage is a threshold value for determining whether or not the power transmission between the drive wheel 77 and the rotor 11 of the first electric motor 10 needs to be interrupted. The set voltage is obtained in advance by a matching experiment or the like and is set to an arbitrary value. When the induced voltage of the first electric motor 10 is equal to or higher than the set voltage, the drive voltage required for driving the first electric motor 10 and the boost ratio in the boost converter 140 are increased accordingly. The boost converter 140 can be set to such a value that the conversion efficiency from the low-voltage DC power to the high-voltage DC power and the conversion efficiency from the DC power to the AC power in the second inverter 120 are deteriorated. The set voltage is such a value that if the induced voltage of the first electric motor 10 is equal to or higher than the set voltage, the rotor 11 cannot generate torque even if the first electric motor 10 is to be powered. Can also be set. The set voltage is stored in advance in the ROM of the control device 100 as a control constant.

  When the induced voltage of the first electric motor 10 that is the driving motor induced voltage is lower than the set voltage (S06, No), the control device 100 determines that the driving motor disconnecting clutch D is in the connected state in step S08. It is determined whether or not. When the driving motor disconnecting clutch D is not in the connected state (S08, No), the control device 100 places the driving motor disconnecting clutch D in the connected state in step S10.

  Thus, when the driving motor induced voltage is not equal to or higher than the set voltage, the control device 100 puts the driving motor disconnecting clutch D into the connected state, so that the first electric motor 10 is immediately powered and the vehicle 1 Can be driven.

  On the other hand, when the induced voltage of the first electric motor is equal to or higher than the set voltage (S06, Yes), in step S12, the control device 100 determines whether or not the drive motor disconnecting clutch D is in a released state. When the drive motor separating clutch D is not in the released state (S12, No), the control device 100 controls the driving motor separating clutch D to the released state in step S14.

  Thus, when the driving motor induced voltage is equal to or higher than the set voltage, the control device 100 controls the driving motor disconnecting clutch D to the released state, and therefore the rotor 11 and the driving wheel 77 of the first electric motor 10 are controlled. Power transmission to and from is interrupted. The rotor 11 is not accompanied by the drive wheels 77, and the occurrence of an induced voltage in the first electric motor 10 is suppressed.

  Next, boost ratio setting control of the boost converter executed by the vehicle control apparatus according to the present embodiment will be described with reference to FIGS. While the vehicle 1 is traveling, the control device 100 repeatedly executes the boost ratio setting control.

  First, in step S22, the control device 100 acquires various control variables. The control variables include the vehicle speed, the accelerator operation amount, the connection / release state of the drive motor disconnection clutch D, the operation state of the first electric motor 10 that is the drive motor (first motor rotation speed and first motor torque), 2 The operation state of the electric motor 20 (second motor rotation speed and second motor torque) and the like are included.

  In step S24, the control device 100 determines whether or not the drive motor disconnecting clutch D is in a released state. That is, the control device 100 determines whether or not an induced voltage is generated when the rotor 11 of the first electric motor 10 that is a drive motor is rotated by the drive wheels 77.

  When the driving motor disconnecting clutch D is not in the released state (No in S24), the control device 100 is required to cause the first electric motor 10 that is the driving motor to be generated in the rotor 11 in step S26. Power (hereinafter referred to as drive motor required power) is calculated. The drive motor required power can be calculated from the vehicle speed, the accelerator operation amount, and the like.

  In step S <b> 28, the control device 100 calculates a drive motor required voltage based on the calculated drive motor required power. In the present embodiment, the drive motor required voltage is a DC voltage required to be applied to the first inverter 110 that supplies AC power to the first electric motor 10.

  On the other hand, when the driving motor separating clutch D is in the released state (S24, Yes), that is, the rotor 11 is not rotated around the driving wheel 77, and the generation of the induced voltage in the first electric motor 10 is suppressed. If it is determined that the required power for the drive motor is calculated (S26) and the required generator power is not calculated (S28), the process proceeds to step S30.

  In step S30, control device 100 calculates mechanical power required to be generated in rotor 22 by second electric motor 20 that mainly operates as a generator (hereinafter referred to as generator required power).

  In step S32, control device 100 calculates a generator required voltage based on the calculated generator required power. In this embodiment, the generator required voltage is a DC voltage that is required to be applied to the second inverter 20 that supplies AC power to the second electric motor 20 that mainly operates as a generator.

  In step S34, control device 100 sets a boost ratio in boost converter 140 and causes boost converter 140 to perform a boost process at the boost ratio. Thereafter, the process returns to step S22.

  When the drive motor disconnecting clutch D is not in the disengaged state (S24, No), the control device 100 is a voltage required to be applied to the first inverter 110 provided corresponding to the first electric motor 10. In consideration of both “driving motor required voltage” and “generator required voltage” required to be applied to second inverter 120 provided corresponding to second electric motor 20, boost converter 140 Set the boost ratio. Specifically, the drive motor request voltage and the generator request voltage are compared, and the boost ratio is set in accordance with the higher request voltage.

  On the other hand, when the drive motor separating clutch D is in the released state (S24, Yes), that is, the rotor 11 is prevented from being rotated around the drive wheel 77, and an induction voltage is prevented from being generated in the first electric motor 10. In this case, control device 100 sets the boost ratio in boost converter 140 in consideration of only the generator required voltage without considering the drive motor required voltage. Specifically, the boost ratio is set according to the generator required voltage.

  As described above, the vehicle 1 according to the present embodiment includes a plurality of drive motors (first electric motors) 10 that are electric motors that mainly output mechanical power from the rotor 11 toward the drive wheels 77. Corresponding to each of the electric motors 10, 20, the booster circuit (boost converter 140) for boosting the electric power from the power storage device 130 that stores the electric power supplied to the electric motors 10, 20, respectively. Provided and connected in parallel to the booster circuit of the common booster converter 140, and converts the power received from the booster circuit (boost converter 140) into the power supplied to the corresponding electric motors 10 and 20, respectively. As power conversion circuits, the first inverter 110 and the second inverter 120 are provided.

  Further, the vehicle 1 includes a drive motor separating clutch D that is a clutch capable of interrupting power transmission between the drive wheels 77 and the rotor 11 of the drive motor (first electric motor) 10, and a machine from the drive wheels 77. Between the drive wheel 77 and the rotor 11 of the drive motor 10 when the induced voltage generated by the rotation of the rotor 11 of the drive motor (first electric motor) 10 receiving the dynamic power is equal to or higher than the set voltage. And a control device 100 for controlling the drive motor separating clutch D to a disengaged state so that the power transmission is cut off. By controlling the clutch D to the disengaged state, the rotor 11 is not accompanied by the drive wheel 77, and a high induced voltage is suppressed from being generated in the drive motor 10, and at a higher value than the induced voltage. “Drive motor required voltage”, which is a voltage that is set and is required to be applied to the first inverter 110 including the power conversion circuit provided corresponding to the drive motor 10, is high. Setting to a value can be suppressed. An increase in the step-up ratio in the step-up circuit of step-up converter 140 that is set to a high value among the plurality of required voltages can be suppressed. Further, by suppressing the boost ratio in boost converter 140, in power converter circuit (second inverter) 120 of another electric motor (second electric motor) 20 connected in parallel to boost converter 140. The step-down ratio can be suppressed.

  Further, in the vehicle 1 according to the present embodiment, the control device 100 performs power conversion provided for each of the electric motors 10 and 20 including the driving motor 10 when the driving motor disconnecting clutch D is in the connected state. The boost ratio in the boost circuit of the boost converter 140 is set based on each required voltage required to be applied to each of the inverters 110 and 120 including the circuit, that is, the “driving motor required voltage” and the “generator required voltage”. To do. On the other hand, when the drive motor disconnecting clutch D is in the released state, “drive” is a required voltage that is required to be applied to the power conversion circuit (first inverter 110) provided corresponding to the drive motor 10. The boost ratio in the booster circuit is set based on the “generator request voltage” that is a request voltage that is required to be applied to another power conversion circuit (second inverter 120) without considering the “motor request voltage”. It was supposed to be. When the drive motor disconnecting clutch D is in the released state, the rotor 11 does not follow the drive wheel 77 and a high induced voltage does not occur in the first electric motor 10, so the drive motor required voltage is also low. Since it becomes a low value, the step-up ratio in the step-up converter 140 does not need to consider the driving motor separating clutch D. The step-up ratio in step-up converter 140 can be set considering only the “generator required voltage” of second inverter 120 corresponding to second electric motor 20 that is an electric motor other than the driving motor.

  In the present embodiment, the vehicle 1 includes a first electric motor 10 that mainly outputs mechanical power toward the drive wheels 77 and a second electric motor 20 that mainly operates as a generator. However, the aspect of the electric motor of the vehicle to which the present invention can be applied is not limited to this. In the present invention, a power conversion circuit is provided for each of a plurality of electric motors, and the power conversion circuit is connected in parallel to a common booster circuit, and at least one of the plurality of electric motors is mainly driven wheels. Any drive motor that outputs mechanical power from the rotor toward the head can be applied. For example, the present invention can be applied to a vehicle including a plurality of drive motors that mainly output mechanical power from a rotor toward drive wheels. For example, the present invention can be applied to a vehicle including a front wheel driving motor and a rear wheel driving motor, and a vehicle including an in-wheel motor for each driving wheel.

  In the present embodiment, the first electric motor 10 and the second electric motor 20 are permanent magnet AC synchronous motors, and the electric power from the booster circuit of the boost converter 140 is supplied to the corresponding electric motors 10 and 20, respectively. Although the inverters 110 and 120 that convert DC power from the boost converter 140 into AC power are used as the power conversion circuit that converts the power to be supplied, the mode of the power conversion circuit is not limited to this. . The power conversion circuit of the present invention is provided corresponding to each electric motor, is connected in parallel to a common booster circuit, and supplies power from the booster circuit to the corresponding electric motor. For example, a DC motor may be used as an electric motor including a driving motor, and a DC chopper that changes an average voltage applied to the DC motor may be used as a power conversion circuit.

  In the present embodiment, the plurality of electric motors are the first electric motor 10 that is a driving electric motor and the second electric motor 20 that mainly operates as a generator, but the present invention is applicable. The aspect of “a plurality of electric motors” is not limited to this. The electric motor of the present invention only needs to be supplied with power from a power conversion circuit connected in parallel to a common booster circuit. For example, as an electric motor other than a drive motor, a compressor of an air conditioner The driving electric motor may be supplied with power from the power conversion circuit of the present invention.

A connection clutch B speed increasing brake C planetary gear side disconnection clutch D drive motor disconnection clutch 1 vehicle 5 internal combustion engine 10 first electric motor (drive motor)
11 Rotor of first electric motor 20 Second electric motor (power generation motor)
22 rotor of second electric motor 30 planetary gear device (power split mechanism)
33 planetary carrier of planetary gear unit 35 first planetary pinion of planetary gear unit 36 first sun gear of planetary gear unit 44 ring gear of planetary gear unit 50 speed increasing mechanism 51 second planetary pinion (speed increasing mechanism) of planetary gear unit
52 Second sun gear (speed increasing mechanism) of planetary gear unit
60, 80 Propulsion shaft 70, 90 Differential device 77, 99 Drive wheel 100 Vehicle control device (control device, control means)
110 First inverter (power converter, power conversion circuit)
120 Second inverter (power converter, power conversion circuit)
130 Power Storage Device 140 Boost Converter (Booster, Booster Circuit, DC / DC Converter)

Claims (5)

A plurality of electric motors, including a drive motor, which is an electric motor that outputs mechanical power from the rotor mainly toward the drive wheels;
A booster circuit that boosts power from a power storage device that stores power supplied to each electric motor;
A power conversion circuit provided corresponding to each electric motor, connected in parallel to a common booster circuit, and converting power received from the booster circuit into power supplied to the corresponding electric motor; ,
A drive motor separating clutch that is a clutch capable of interrupting power transmission between the drive wheel and the rotor of the drive motor;
When the induced voltage generated by the rotation of the rotor of the drive motor in response to the mechanical power from the drive wheel is equal to or higher than the set voltage, the power transmission between the drive wheel and the rotor of the drive motor is interrupted. A control device for controlling the drive motor separating clutch to a released state,
Equipped with a,
The control device applies to other power conversion circuits without considering the drive motor required voltage that is required to be applied to the power conversion circuit of the drive motor when the drive motor separating clutch is in the released state. A vehicle that sets a boost ratio in a booster circuit based on a required voltage that is required to be performed . The vehicle according to claim 1 ,
The drive motor is a first electric motor in which the rotor rotates in conjunction with the drive wheel when the drive motor disconnecting clutch is in a connected state.
One of the plurality of electric motors is a second electric motor that mainly operates as a generator,
A boost converter that includes a booster circuit, boosts DC power from the power storage device, and converts it into DC power having a higher voltage;
A first inverter that includes a power conversion circuit and converts DC power from the boost converter into AC power supplied to the first electric motor;
A second inverter that includes a power conversion circuit and converts DC power from the boost converter into AC power supplied to the second electric motor;
Provided with the vehicle. The vehicle according to claim 1,
The set voltage is a vehicle in which the conversion efficiency of a power conversion circuit that supplies current to an electric motor other than the drive motor in the power conversion circuit is a predetermined value or less. The vehicle according to claim 1,
The vehicle, wherein the set voltage is a value that is equal to or less than a predetermined value at which torque generated in the rotor of the drive motor can be powered. A plurality of electric motors including a driving motor that is an electric motor that outputs mechanical power from a rotor mainly toward a driving wheel, a booster circuit that boosts power from a power storage device that stores the power, and each electric motor A power converter circuit that is provided correspondingly and is connected in parallel to a common booster circuit and that converts power received from the booster circuit to power supplied to a corresponding electric motor, respectively, is used in a vehicle. A vehicle control device capable of controlling a drive motor separating clutch that is a clutch capable of interrupting power transmission between the drive wheel and the rotor of the drive motor,
When the induced voltage generated by the rotation of the rotor of the drive motor in response to the mechanical power from the drive wheel is equal to or higher than the set voltage, the power transmission between the drive wheel and the rotor of the drive motor is interrupted. The drive motor disconnect clutch is controlled to be released ,
When the drive motor separation clutch is in the released state, it is required to be applied to other power conversion circuits without considering the drive motor required voltage required to be applied to the power conversion circuit of the drive motor. based on the required voltage is to set the step-up ratio in the booster circuit, car dual controller.

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